The infectious hypodermal and hematopoietic necrosis virus (IHHNV) is an economically significant pathogen of penaeid shrimp grown in mariculture. The virus has a broad host species range; it may kill up to 90% of the juveniles of certain penaeid shrimp species.
The penaeid shrimp virus IHHNV has been isolated from infected shrimps. ( Y. N. Lu, P. C. Loh, and J. A. Brock, "Isolation and Characterization of the Infectious Hypodermal and Hematopoietic Necrosis Virus of penaeid Shrimp," 89th Annual Meeting, American Society for Microbiology, New Orleans, La., May 14-18, 1989.) The virus has been found to have a buoyant density in CsCl of 1.33 g/cm.sup.3. Electron microscopical studies have shown the virus to exist as isometric particles with a size of 19.+-.1 nm. Also, colorimetric analyses of the viral nucleic acid by the orcinol test have shown that the virus contains RNA. (Shatkin, A. J. in "Fundamental Techniques in Virology", Habel, K. and Salzman, N. P., eds. p. 23, Academic Press, N.Y. (1969)).
Previously, biological and biochemical studies of IHHNV have been limited because the virus could only be grown in young post-larval shrimps using an indicator shrimp bioassay. (Lightner et al., J. World Maric. Soc. 14:212-225, 1983). Consequently, the lack of an in vitro cell culture method for IHHNV made it difficult to develop serologically based methods useful for the rapid detection of the virus in shrimp stocks. Additionally, the only available method of IHHNV assay formerly available, the in vivo indicator shrimp bioassay procedure, is expensive, time consuming (on the order of days to weeks), and requires highly trained personnel.
The growth of crustacean virus according to the present invention provides a readily available source of cultured virus useful for development of immune sera for the rapid detection of virus in its habitat.